London Marathon to become a two-day record-setting event in 2027: what changes and why

Since 1981, the London Marathon has been run every year on the classic 42.195-kilometre course from Greenwich to The Mall on a single day. According to Sky Sports, the 2027 edition will break that pattern as a one-off: a special format that spreads the race across two consecutive days.

The data behind the format change covers four years. Application numbers in 2023, 2024 and 2025 came in at 485,000, 537,000 and 612,000 respectively; the 2026 figure topped 720,000. That growth shows the gap between existing capacity (around 49,000 runners) and the demand for the race is widening structurally.

The 2027 format will not split the two days by category but will instead run the same course twice. About half the registered runners (roughly 30,000) will run on Saturday and the other half (again about 30,000) plus the elite race field (around 130) will run together on Sunday. Total participation in the event reaches around 60,000.

Organisers told Sky Sports the decision is aimed both at meeting demand and easing the city's load. With 50,000 runners stacked into a single day, central London's transport network comes under serious strain; spreading the load over two days balances the load distribution and creates a smoother ramp-up and ramp-down.

The question of which day the elite race will run on is critical. According to the official statement, the elite men's and women's races will be on Sunday; Saturday is reserved for charity runners, fun runners and clubs. That decision is consistent with the broadcast rights remaining anchored to Sunday's international prime-time window.

London Marathon chief executive Hugh Brasher said in his statement: "This is the most ambitious evolution of our event to date." Brasher added that no decision has been taken yet on making the format permanent from 2028 onwards; the 2027 data will be the central reference point.

The event represents a historic step on another dimension: accessibility. The two-day spread enables a wider range of categories for runners with physical disabilities, and a separate category has been added. Wheelchair races will be run on Saturday afternoon.

Within the current urban marathon landscape, London is structurally one of the world's six major marathons alongside Boston, New York, Chicago, Berlin and Tokyo. The 2027 edition will be the first two-day format in that six-marathon family.

The experimental format will feed through into city-wide tourism revenue. According to Visit London estimates, shifting from one day to two will increase total additional event-linked spending by around £47 million; hotel bookings for the Saturday night are already starting with a forecast 18% demand premium.

The big picture: the 2027 two-day London Marathon is framed as a one-off experiment, but the chance of it becoming permanent is high. Demand pressure, logistical load and the city's tendency toward phased access mean London is positioning itself as a test pilot for a wider reframing of mass-participation marathons.